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GCC 4.8.0 Release Marks Completion of C++ Migration
hypnosec writes "GCC 4.8.0 has been released (download), and with it, the developers of the GNU Compiler Collection have switched to C++ as the implementation language, a project the developers have been working for years. Licensed under the GPLv3 or later, version 4.8.0 of the GCC not only brings with it performance improvements but also adds memory error detector AddressSanitizer, and race condition detection tool the ThreadSanitizer. Developers wanting to build their own version of GCC should have at their disposal a C++ compiler that understands C++ 2003."
From the changelog: "A new general optimization level, -Og, has been introduced. It addresses the need for fast compilation and a superior debugging experience while providing a reasonable level of runtime performance. Overall experience for development should be better than the default optimization level -O0."
This actually sounds really attractive to me... I'll have to try it out.
I remember seeing a pretty cool 8080 program to zero memory. It went something like:
LXI BC, 0000
LXI HL, 0009
LXI SP, 0008
PUSH BC
PCHL
HL, BC, and SP (the stack pointer) are all 16-bit registers, and the first three instructions occupy 0x0000-0x0008 in memory. PUSH BC is one byte at 0x0009, and PCHL (another one-byte instruction) sets the program counter to the value of HL; essentially it allows you to jump to the address contained in the HL register. The PUSH operation decremented the stack pointer before storing each of the bytes, so you would set the stack pointer to one higher than the highest address you wanted to overwrite. Because the 8080 was little-endian, address 0x0008 was the upper byte of the third instruction's numeric value - it was already zero (if it were big-endian you could just throw in a NOP to get it to align properly). The final PUSH operation - after the program had cycled through all of memory - wiped out the PUSH BC and PCHL operations, and the computer would go to all NOPs.